Yes, Felicity. You can add the sales tax information on the statement by turning on the List each transaction including all detail lines option from the Account and settings page.
Here's how:
- Go to the Gear icon, then Account and settings.
- Navigate to the Sales tab.
- Scroll down and select the Statements field.
- Click the List each transaction including all detail lines option.
- Hit Save, then Done.

Once enabled, your client will receive a breakdown of the invoice item's amount and the sales tax included in the entry.
For reference, this is how the statement looks after you send it to the client:

You can also access this link to gather more details about managing customer statements in QuickBooks: Create and send customer statements in QuickBooks Online.
Additionally, you may store a backup copy of your sales forms and statements on your device's internal memory. Explore this article for further information: Download and save sales forms and statements in QuickBooks Online.
Don't hesitate to return to this thread once you have more questions about customer statements in QuickBooks.